1. Technical Field
The present invention relates to a steering wheel, in which when an impact is exerted on conveyances, such as vehicles, from the front thereof, an airbag apparatus for protecting a driver from the impact is provided.
2. Related Art
One aspect of steering wheels of such a type is for example known, in which an airbag apparatus is mounted on a core metal via a horn switch mechanism for activating a horn device as described in JP-A-2013-71626.
As shown in FIG. 12, the horn switch mechanism 50 includes a supporting member 51, a slider 52, a cap member 53 and a movable side contact 54. The supporting member 51, which is formed of an electrically conductive metal material, is locked on the core metal 55 and extends rearward. A rear end of the supporting member 51 constitutes a fixed contact 51a. The slider 52, which is formed of an insulating resin material, is slidably disposed outside the supporting member 51 and urged rearward by a spring 59. The cap member 53 is formed of an insulating resin material and covers a rear end of each of the supporting member 51 and the slider 52. The movable side contact 54 is formed of an electrically conductive metal material and disposed between the cap member 53 and the slider 54. The movable side contact 54 is electrically contacted to the horn device 57 via a bag holder 56 and the like.
In the steering wheel 58 provided with the horn switch mechanism 50, when the airbag apparatus is not pressed down, the movable side contact 54 is located rearward apart from of the fixed contact 51a of the supporting member 51. Thus, electrical communication between both contacts 51a and 54 is interrupted and thus the horn device 57 is not activated.
Contrary, when the airbag apparatus is pressed down, a force exerted on the airbag apparatus is transferred to the movable side contact 54 and the slider 52 via the cap member 53. The slider 52 is pressed by the cap member 53 and the slider 52 is slid forward against the spring 59. Also, when the movable side contact 54, together with the cap member 53, is moved forward to be contacted and electrically communicated with the fixed contact 51a of the supporting member 51, the horn device 57 is activated.
Thus, in addition to exhibiting a function of being locked on the core metal 55 and a function of supporting the airbag apparatus to be movable relative to the core metal 55 in a front and rear direction, the supporting member 51 also serves as the fixed contact 51a. Therefore, the number of components in the steering wheel can be reduced, thereby obtaining simplification of the configurations thereof.
However, according to JP-A-2013-71626, a configuration in which the slider 52 is indirectly contacted with the cap member 53 via the movable side contact 54 is employed. Therefore, when the slider 52 made of resin is brushed against the movable side contact 54 made of metal, a part of the slider 52 contacted with the movable side contact 54 is cut to generate resin powders. Also, if resin powders are accumulated and thus an insulating layer is formed between the movable side contact 54 and the fixed contact 51a, there is a risk that, when the airbag apparatus is pressed down, electrical communication between the movable side contact 54 and the supporting member 51 is disturbed.
Accordingly, the present invention has been made keeping in mind the above problems, and an object thereof is to provide a steering wheel in which generation of resin powders due to contact of a slider with a movable side contact can be prevented.